Y/Pb/Pr was invented was to save on bandwidth, only the Y (luminance) carries the full resolution while the Pb and Pr need only carry much less, it is half the resolution both horizontal and vertical for DVD, DTV and U.S. HDTV.

RGB is theoretically better but at the same more expensive and was impractical for over the air broadcasting. RGB (which VGA is) is superior for computer data, but that only has to travel a few feet from PC to monitor. There is no common video source material, including HDTV, for which RGB will exhibit its superiority.